/*
 * ProGuard -- shrinking, optimization, obfuscation, and preverification of Java bytecode.
 *
 * Copyright (c) 2002-2018 GuardSquare NV
 *
 * This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public
 * License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later
 * version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with this program; if not, write to the Free
 * Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
package proguard.classfile.editor;

import proguard.classfile.*;
import proguard.classfile.attribute.*;
import proguard.classfile.attribute.visitor.BootstrapMethodInfoVisitor;

/**
 * This BootstrapMethodInfoVisitor adds all bootstrap methods that it visits to the given target class, creating a
 * bootstrap methods attribute if necessary.
 */
public class BootstrapMethodsAttributeAdder implements BootstrapMethodInfoVisitor {
    private final ProgramClass targetClass;
    private final ConstantPoolEditor constantPoolEditor;
    private BootstrapMethodInfoAdder bootstrapMethodInfoAdder;

    /**
     * Creates a new BootstrapMethodsAttributeAdder that will copy bootstrap methods into the given target class/
     */
    public BootstrapMethodsAttributeAdder(ProgramClass targetClass) {
        this.targetClass = targetClass;
        this.constantPoolEditor = new ConstantPoolEditor(targetClass);
    }

    /**
     * Returns the index of the most recently added bootstrap method.
     */
    public int getBootstrapMethodIndex() {
        return bootstrapMethodInfoAdder.getBootstrapMethodIndex();
    }

    // Implementations for BootstrapMethodInfoVisitor.

    public void visitBootstrapMethodInfo(Clazz clazz, BootstrapMethodInfo bootstrapMethodInfo) {
        // Make sure we have a bootstrap methods attribute adder.
        if (bootstrapMethodInfoAdder == null) {
            // Make sure we have a target bootstrap methods attribute.
            AttributesEditor attributesEditor = new AttributesEditor(targetClass, false);

            BootstrapMethodsAttribute targetBootstrapMethodsAttribute =
                (BootstrapMethodsAttribute)attributesEditor.findAttribute(ClassConstants.ATTR_BootstrapMethods);

            if (targetBootstrapMethodsAttribute == null) {
                targetBootstrapMethodsAttribute = new BootstrapMethodsAttribute(
                    constantPoolEditor.addUtf8Constant(ClassConstants.ATTR_BootstrapMethods), 0,
                    new BootstrapMethodInfo[0]);

                attributesEditor.addAttribute(targetBootstrapMethodsAttribute);
            }

            // Create a bootstrap method adder for it.
            bootstrapMethodInfoAdder = new BootstrapMethodInfoAdder(targetClass, targetBootstrapMethodsAttribute);
        }

        // Delegate to the bootstrap method adder.
        bootstrapMethodInfoAdder.visitBootstrapMethodInfo(clazz, bootstrapMethodInfo);
    }
}